This invention relates to a time-lag fuse in which a fuse element is wound on an elongated core member having high-thermal conductivity.
Time-lag fuses used in the past have some defects such that they are inferior in temperature characteristics to widely vary in time-lag characteristics. As an improvement developed and eliminate such defects, there are time-lag fuses in which a fuse element is spirally wound on an elongated core member made of a sintered ceramic material. This invention is an improvement made further on such time-lag fuse as a fuse for motor protection.
One object of this invention is to provide a time-lag fuse in which a fuse element is wound on an elongated core member having high thermal conductivity, said fuse protecting a motor without melting even when a large drive current generated at the initial stage of the current flow.
Another object of this invention is to provide a time-lag fuse having excellent time-lag characteristics in which the elongated core member is made of a material comprising high weight percent aluminum oxide.